A solid-state imaging device may conventionally adopt the measures for enlarging a pixel, for example, in order to pick up an image with a high sensitivity. In the case where the size of an image sensor is increased due to the enlargement of the pixel, a long distance from a lens to a light receiving surface (a focal distance) is secured, thereby making it difficult to reduce the thickness of a camera module.
Most image sensors adopt the Bayer matrix in which a red (R) pixel and a blue (B) pixel are arranged on one diagonal line in a pixel block of a 2×2 matrix whereas two green (G) pixels are arranged on the other diagonal line. There has been conventionally proposed an image sensor in which one of G pixels in a pixel block of a 2×2 matrix is replaced with a white (W) pixel in order to pick up an image with a high sensitivity. The W pixel captures a white light. The W pixel is arranged so as to sufficiently secure the signal electric charge amount of a luminance signal.
The W pixel captures a light at a wider wavelength range than those of the other color pixels, and therefore, saturation of an output with respect to an intensity of a light incident into a pixel cell occurs earlier than in the other color pixels. Since the output with respect to the intensity of the incident light is saturated in the W pixel, the image sensor provided with the W pixel may achieve a satisfactory sensitivity with respect to each of colors. Moreover, many lights are captured into the W pixel, and therefore, a crosstalk is liable to occur in the W pixel because the light leaks out to the other color pixels adjacent to the W pixel. The image sensor provided with the W pixel has experienced the problem of degradation of color reproducibility caused by the crosstalk.